The present invention relates to a hydraulically damped resilient or elastic mounting, especially for the engines of motor vehicles. The mounting includes a first connector that bears against a second connector via an essentially annular elastomeric spring element. A connecting rod is secured to the first connector and extends concentrically into a pot-shaped working cylinder that is securely connected to the second connector and is filled with a flowing or hydraulic medium. A damping disk is mounted with axial play on the free end of the connecting rod. The damping disk is axially movably disposed in the working cylinder in such a way that the damping disk is disposed essentially perpendicular to the axis of the working cylinder, and an annular gap exists between the damping disk and the inner wall of the working cylinder.
Mountings of this general type, which are provided in particular to support the engines of motor vehicles, are known, for example, from U.S. Pat. No. 3,368,807 Thrasher dated Feb. 13, 1968 and U.S. Pat. No. 4,610,438 Eberhard et al dated Sep. 9, 1986 the latter of which belongs to the assignee of the present application. The heretofore known mountings of the aforementioned general type contain as hydraulic medium a liquid having a viscosity that is generally in the order of magnitude of 100,000 cp (centipoise). The damping effect of these heretofore known mountings is derived by having a disk, which is disposed perpendicular to the direction of deflection, carry out displacement operations in the high-viscosity hydraulic medium. The known mountings will therefore be designated as displacement mountings in the following discussion. Just like the so-called hydraulic mountings, which operate pursuant to a basically different principle, and are known, for example, from U.S. Pat. No. 4,159,091 LeSalver et al dated June 26, 1979, the displacement mountings are intended on the one hand for absorbing the so-called acoustic, i.e. high-frequency, motor vibrations, so that the latter are not transmitted to the rest of the vehicle, and on the other hand for rapidly suppressing low-frequency vibrations by intense damping.
Although the aforementioned so-called displacement mountings are distinguished by a straightforward and economical type of construction, and also permit a tension stop to be integrated therein in a simple manner, these known displacement mountings have the drawback that the absorption of the acoustic vibrations was limited due to the fact that the shearing stresses from the engine were introduced into the high-viscosity hydraulic medium, and were transmitted via this medium to the body of the vehicle.
It is therefore an object of the present invention to provide an elastic mounting that has the advantages of the heretofore known so-called displacement mountings, and at the same time permits not only a practically complete absorption of the so-called acoustic low-frequency, longstroke vibrations, but also an effective damping of these vibrations.